I took the MAG-40 class in SLC last year. I would recommend it to anyone. I would summarize the class as a Masters degree in when to shoot, and a Bachelor's degree in how to shoot.
The classroom portions covers the legal aspects of self defense - when you would be justified to shoot, how to interact with suspects, witnesses, and the police after a shooting, and how to defend yourself in court if you are prosecuted. I came away from the classroom portion with 40 pages of single-spaced typed notes chock-full of valuable information. Many of the people in the class with us made statements afterwards that they can't believe the ever carried a gun without knowing all of this stuff.
The shooting portion of the class focuses on key fundamentals like grip, stance, trigger control, one handed shooting, weak hand shooting, shooting from kneeling potions, etc. Not super advanced, but it will serve to help fine-tune any shooters abilities.
By the end of the course you will have taken a 60-round shooting qualification test based on various aspects of long-established police/FBI qualification tests, and a written test based on the key concepts taught in the classroom portion. These are saved by the Massad Ayoob Group, and if you are ever prosecuted for a true self-defense case, can be used to show that you were proficient with your firearm, and that you have beyond the ken knowledge of self defense concepts and the legality of using such.
Additionally, if any MAG class graduate is involved in a self defense shooting, Mas can be hired as an expert material witness on your behalf. In that role he can spend up to 40 hours teaching the jury what you have been taught, do a rebuttal of the prosecution, and be invaluable in other ways to your lawyer. Contrary to popular belief, that jury won't be a jury of your peers - anyone that is likely to have any simpathy for you (i.e. gun owners, etc) will have been weeded out during the jury selection process. That expert testimony is key, as are the on-file proof of your proficency and knowledge the the qualification/test results represent.
In the end, while $800 was a big stretch for me to spend, I haven't had any buyers remorse. I view that money as money well spent/invested in the future safety of me and my family.
Primary: Springfield TRP 4.25" 1911 - Hornady Critical Defense - Concealment Solutions IWB
BUG: Sig P238 with Hornady Critical Defense in a Concealment Solutions AIWB